Find the area of a triangle two sides of which are `18 cm` and `10 cm` and the perimeter is `42 cm.`

Explanation

To find the area of a triangle with two sides measuring 18 cm and 10 cm, and a perimeter of 42 cm, we can follow these steps:

### Step 1: Identify the sides of the triangle
Let the sides of the triangle be:
- \( A = 18 \, \text{cm} \)
- \( B = 10 \, \text{cm} \)
- \( C = ? \) (unknown side)

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